Ramsey-coherent population trapping Cs atomic clock based on lin∥lin optical pumping with dispersion detection**Project supported by the National Key Research and Development Progress of China (Grant No. 2016YFA030210) and the Initiative Program of the State Key Laboratory of Precision Measurement Technology and Instruments, China.

Abstract

A Cs vapor cell-based atomic clock that uses a lin∥lin pumping scheme with dispersion detection is reported. This atomic clock shows potential for high performance because of its high contrast pumping scheme, and for miniaturization because of its simple architecture. The experimental setup and optimal operating parameters for the clock are introduced. The current fractional frequency stability is measured to be up to 20 s and reaches at 200 s. We have thoroughly investigated the related noise sources that affect clock frequency stability at the 1 s and 100 s levels. The investigation shows that the laser frequency noise limits the clock frequency stability significantly. The clock performance can be further improved by technically upgrading the laser frequency stabilization setup.